Cornwall
Rear extensions in Truro
From the first measured visit to building control sign-off, we handle rear extensions in Truro under one contract.
Truro is in Cornwall, with postcode districts including TR1. The nearest places we also cover are Falmouth (7.7 miles) and Redruth (7.8 miles).
Book a free site visit
Tell us about the house and we'll call to arrange a free, no-obligation visit.
Rear extensions we build in Truro
- Single-storey rear extensions
- Two-storey rear extensions
- Kitchen-diner rear extensions
- Side return extensions
- Wraparound extensions
- Glazed and glass-box rear extensions
- Rear extensions for terraced houses
- Rear extensions for semi-detached houses
- Rear extensions for bungalows
- Rear extension plans and planning applications
Also available across Cornwall:
- Rear extensions for detached houses
- Flat-roof rear extensions
- Pitched and lean-to roof rear extensions
- Knocking through to a rear extension
- Roof lanterns and rooflights for rear extensions
- Permitted development rear extensions
- Larger home extension prior approval (England)
- Building Regulations for rear extensions
Rear extension prices in Truro
South West prices run slightly above our West Midlands baseline; natural stone to match the house is the main variable.
| Example | Guide inc VAT |
|---|---|
| Single-storey, 3 m × 4 m (12 m²) | £23,500–£38,500 |
| Single-storey, 4 m × 6 m (24 m²) | £47,500–£77,500 |
| Two-storey, 3 m × 5 m footprint (30 m²) | £56,000–£84,000 |
| Side return, about 14 m² | £33,500–£55,500 |
| Wraparound, about 25 m² | £57,000–£93,500 |
What are homes in Truro like to extend?
Stone-built and rendered houses are common around Truro, so matching the walling is a design decision in its own right: natural stone, reconstituted stone or a render finish across old and new.
Planning rules for Truro
Under England's householder permitted development rules you can usually add 3 metres at the back of an attached house, or 4 metres on a detached house, without a planning application, as long as the extension stays under 4 metres high and its eaves stay under 3 metres where it is within 2 metres of a boundary.
If 3 or 4 metres is not enough, England's prior approval route allows 6 metres on a terraced or semi-detached house and 8 metres on a detached house for a single-storey rear extension. Neighbours are consulted, the council decides within 42 days, and the fee is £249, rising to £310 from 8 December 2026.
Every rear extension in England needs Building Regulations approval, whether or not planning is needed. You can use the council's building control service or a registered building control approver, by full plans (checked before work, usually within five weeks) or a building notice, and you get a completion certificate at the end.
Nearby towns
FAQ
Questions people ask
How much is a rear extension in Truro?
A 3 m × 4 m single-storey rear extension is about £23,500–£38,500 including VAT at our South West England guide rates; the written price follows a survey.
Do I need planning permission in Truro?
Often not for a single-storey rear extension of up to 3 metres (4 metres on a detached house) under permitted development, or up to 6 or 8 metres with prior approval, unless the house is in a conservation area or its rights have been removed.
Is the site visit in Truro free?
Yes, with no obligation.
Do I need a party wall agreement?
In England, usually yes if the extension is on or near a shared boundary or the foundations are close to a neighbour's building. We serve the notices.